Structure for detachable coupling of containers

ABSTRACT

A container structure is provided for detachable coupling of at least two containers. The detachable coupling structure of a first container includes a top portion with an upstanding perimeter having radial protrusions extending from a surface of the upstanding perimeter, and a container bottom portion having a complementary structure to engage the radial protrusions of the top portion of a second container for the purpose of detachably coupling two or more containers end to end. In one embodiment, two containers placed end to end with their respective structures aligned to be engaged are rotated in opposite directions to fully engage the protrusions of one container with the complementary structure of the other. A rim around the top portion of a container in a second embodiment has a larger diameter than the top portion. The rim may be pushed through a flexible opening into a recess in the bottom of another container.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to containers such as beveragecans and bottles and, more particularly, to structures in such cans andbottles for simply achieving detachable coupling of two or morecontainers.

2. Description of the Related Art

Most typical containers have been produced and commercialized inhandheld sizes that have no means for detachable coupling to each other.Therefore, most of the typical containers having no detachable couplingmeans are separately kept or carried with a person when one or twocontainers need to be kept or carried. This creates a problem that it isvery difficult for a person to keep or carry three or more containerssimultaneously.

As is well known to those skilled in the art, cans are conventionallyformed of iron thin plates or aluminum thin plates, and bottles areconventionally formed of glass, plastics, or metals. Materials forforming containers should be saved from the viewpoint of conservation ofresources. In order to conserve resources, the emptied containers needto be recovered and reproduced. However, since there is difficulty inholding more than one container in each hand, there is a problem thatthey must be collected one by one when gathering them for theirrecycling. Since most of the typical containers have no means forcoupling them to each other, there is no simple means for simultaneouslygathering multiple containers. Thus, the emptied containers are usuallydiscarded separately. Since the typical containers having no detachablecoupling means, they are usually discarded separately in the open air,or scattered in the forest or in the sands. Hence, when the emptiedcontainers separately discarded are collected for recycling, they mustbe picked up one by one when found, and this creates problems forcontainer collectors. Hence, the containers separately discarded in theopen air may be neglected. This not only runs counter to the need forresource saving but also causes environmental pollution.

In the prior art, there have been proposed detachable can couplingstructures and detachable can coupling methods for overcoming the aboveproblems caused by the typical cans having no coupling means. However,the prior art structures and methods for coupling the cans are notpractically used because of their structural problems as will bedescribed later herein.

Japanese Utility Model Laid-open Publication No. Sho. 54-58350 disclosesa can having, at its top and bottom, a screw type coupling structuresfor vertically detachably coupling the cans to each other. However, thiscan causes a hygienic problem in that the contaminants on its topcoupling structure may be introduced into the human body when drinkingthe beverage from the can. That is, the screw type top couplingstructure has recesses between its threads, and contaminants may bepresent in those recesses. In this regard, the contaminants remaining onthe top coupling structure may be directly introduced into the humanbody along with the beverage when drinking the canned beverage, thuscausing a hygienic problem. In addition, each of the top and bottomcoupling structures of the above can is shaped in the form of apredetermined width of annular strip extending from the top periphery orthe bottom periphery of the can. The top and bottom screw type couplingstructures of the can are thus weak in their bending strengths so thatthey are apt to be deformed or bent even when they are subjected to aweak outside shock. When either of the top and bottom couplingstructures of the can is deformed by an outside shock, this can cannotbe coupled to another can at its top or bottom. In this regard, theabove can is attended with a problem in its practical use.

Japanese Utility Model Laid-open Publication No. Sho. 63-1727 disclosesa pair of cans having another type of can coupling structure fordetachably coupling the two cans to each other. In this device, the cancoupling structure comprises a slot flange extending upwardly from thetop periphery of the bottom can to a predetermined length and slitted atpredetermined positions so as to form diametrically opposed lockingslide slots in an L-shape. In order to engage with the above L-shapedlocking slide slots of the bottom can for achieving the detachablecoupling of the cans, the top can is provided with a pair of lockingslide projections extending outwardly from its bottom side at positionscorresponding to the above locking slide slots. In accordance with thisdevice, the two cans or the top and bottom cans are coupled to eachother by bringing the projections of the top can into engagement withthe L-shaped slots of the bottom can. However, when the top periphery ofthe bottom can is partially slitted so as to form the L-shaped lockingslide slots, the can may not achieve the desired hermetical sealing dueto the structural limit of the typical can. Moreover, even when theL-shaped locking slots are formed on the top periphery of the can whileproviding the can with the desired hermetical sealing, another problemis caused by the material of the can. That is, since the can is made ofthe iron thin plate or the aluminum thin plate as described above, theslot flange of the bottom can having the L-shaped slots is apt to bedeformed or bent by an outside shock, thus failing in its engagementwith the projections of the top can. Particularly when the can is madeof the aluminum thin plate, which plate is softer and shows lesselasticity than the iron thin plate, the above problem of bendingdeformation of the slot flange will become worse. Accordingly, thiscoupling structure can not be adapted to typical cans.

U.S. Pat. No. 5,573,133 discloses a can structure for detachablecoupling of at least two cans. The detachable coupling structureincludes a plurality of L-shaped grooves on an outside surface of abottom peripheral ring of each can such that each of them has areceiving portion and a locking portion. The detachable couplingstructures also includes a plurality of projections extending inwardlyfrom an inside surface of a top peripheral flange of each can atpositions corresponding to the grooves. In order to attach the canstogether using this detachable coupling structure, the projections needto be aligned with an end of the L-shaped grooves, inserted into thegrooves until the projection reaches the turn in the L-shaped groove andthen moved down the length of the L-shaped groove to the lockingposition.

People of all ages transport and consume beverages in beveragecontainers in many parts of the world irrespective of the above problemscaused by the prior art containers. The frequent and widespread use ofthe prior art beverage containers presents a significant need forproposing a new beverage container. Such a new container should have anew structure for overcoming the above problems of the prior artcontainers and should provide for detachably coupling the containers toeach other when keeping and carrying them with the person. The worldwideneed to conserve resources promotes such a proposal of the newcontainers having the new detachable coupling structure suitable formaking the emptied containers easily and simply recovered for theirrecycling.

OBJECTS OF THE INVENTION

It is, therefore, an object of the present invention to provide acontainer with a structure for detachable coupling which easily achievesthe desired manual detachable coupling of containers to each otherwithout addition of another means, thus facilitating the keeping orcarrying of two or more cans in the user's hands, the coupling structurealso allows repeated detachable coupling of the containers withoutcausing any container structure problems.

It is another object of the present invention to provide a containerwith a structure for detachable coupling of containers, in which thestructure easily, manually, detachably couples the containers to eachother when discarding and keeping the containers after emptying thecontainers of their contents, thus allowing the emptied containers to bediscarded or kept while being coupled to each other, and thus allowingthe emptied containers to be more efficiently recovered for theirrecycling and improving the recovery rate of the emptied containers.

It is still another object of the present invention to provide acontainer structure for detachable coupling of containers which iseasily adapted to typical containers without changing either the shapeor the structure of the typical containers, which is easily put topractical use, and which may be efficiently used in mass production.

It is still another object of the present invention to provide acontainer with a structure for detachable coupling of containers whichcan be produced in mass production by a simple process and with low costdue to its simple construction.

It is still another object of the present invention to provide acontainer with a structure for detachable coupling of containers whichsaves cost since its coupling structure, while achieving the aboveobjects, nevertheless causes no or very little increase of the amount ofmaterial used in the container.

It is still another object of the present invention to provide acontainer with a structure for detachable coupling of containers, inwhich the coupling structure is hygienically favorable to a persondrinking from the contained beverage while directly touching thepredetermined position of the flange of the container with his or herlips.

It is still another object of the present invention to provide acontainer with a structure for detachable coupling of containers, whichcoupling structure gives no or little bad influence upon the structuralstrength of the container because the coupling structure does notcomprise a portion slitted into the container body, a portion welded onthe container body, or a portion riveted into the container body.

SUMMARY OF THE INVENTION

In order to accomplish some or all of the above objects, the presentinvention provides a container with complementary detachable couplingstructures on opposite ends such that a container may be detachablycoupled with similar containers at both ends. On a first end of thecontainer is a perimeter structure extending longitudinally beyond thecenter of the end face of the container, such that the perimeterstructure has a perimeter inner diameter. On the second end of thecontainer is an extended end structure with an end outside diametersmaller than the inner diameter of the perimeter structure on the firstend. To detachably couple two containers each possessing the twostructures, the extended end structure on the second end of onecontainer is inserted into the perimeter structure on the first end ofthe other container in a manner which engages complementary detachablecoupling mechanisms of the respective structures. The containers aredetached by disengaging the respective complementary structures andwithdrawing the extended end structure of one container from theperimeter structure of the other container.

In accordance with a first embodiment of the invention, a firstcontainer having each of the above described complementary structures isdetachably coupled to a second container also having each of the abovedescribed complementary structures. The structure at the first end ofthe first container includes one or more radial protrusions which, whenthe two containers are longitudinally aligned and inserted together, asdescribed above, engage corresponding circumferentially oriented voidsor depressions in the complementary structure on the second end of thesecond container. Upon aligning the containers to engage the respectivestructural features, rotating the two containers in opposite directionswith respect to the longitudinal axis of the containers, and furtherengaging the radial protrusions of the first container with thecorresponding voids or depressions of the second container, the twocontainers are securely coupled. The coupling of the containers isdetached by rotating the containers in directions with respect to eachother which are opposite from the directions used for engaging thecontainers, and withdrawing the inserted extended end structure of onecontainer from the perimeter structure of the other container.

In accordance with a second embodiment of the invention, a firstcontainer has an extended end structure on a first end of the container,the extended end structure has a first outer diameter, and the firstcontainer having a ridge around the outer periphery of the extended endstructure, the ridge having a second outer diameter which is larger thanthe first diameter. A first container is detachably coupled to acomplementary perimeter structure on a second end of a second container.The perimeter structure, having a first inner diameter, includesflexible protrusions extending radially inwardly from the inner surfaceof the perimeter structure toward the center of the container, therebycreating a flexible opening with a second inner diameter that is smallerthan the first inner diameter of the perimeter and smaller than thesecond outer diameter of the ridge on the extended end structure. Uponaligning and inserting the extended end structure of a first containerinto the flexible opening of the perimeter structure of a secondcontainer, the ridge around the extended end structure contacts theflexible opening. By applying sufficient force, the flexible protrusionsdefining the inner diameter are bent until the ridge is forced into andthrough the flexible opening of second inner diameter. Once the entirethickness of the ridge has passed through the flexible opening, theflexible protrusions either re-extend to their original, undeformedstate, if the second inner diameter is larger than the first outerdiameter of the extended end structure, or they extend inward until theycontact the extended end structure at the first outer diameter. Thecoupling of the containers may be detached by forcibly withdrawing,against the resistance of the flexible protrusions, the insertedextended end structure of the first container from the perimeterstructure of the second container.

The detachable coupling of containers, according to either embodiment ofthe present invention, may be repeatedly performed without damage to therespective structures or the containers. A plurality of containers maybe detachably coupled by attaching additional containers at either endof previously coupled containers, according to both of the twoembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features, and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings.

FIG. 1 is a top view of a first example of a can with a structure fordetachable coupling of containers in accordance with a first embodimentof the present invention.

FIG. 2 is a side view of the bottom of the can of FIG. 1.

FIG. 3 is a partially enlarged sectional view of two cans of the firstexample of the first embodiment, as in FIG. 1, showing the coupled stateof the cans.

FIG. 4 is a side view of the bottom of a second example of a can with astructure for detachable coupling of containers in accordance with thefirst embodiment of the present invention.

FIG. 5 is a bottom view of the can of FIG. 4.

FIG. 6 is a partially enlarged sectional view of two cans of the secondexample of the first embodiment, as in FIG. 4, showing the coupled stateof the cans.

FIG. 7 is a perspective view of a first end of a container with astructure for detachable coupling of containers in accordance with afirst example of a second embodiment of the present invention.

FIG. 8 is a perspective view of the second end of a container with astructure for detachable coupling of containers in accordance with afirst example of a second embodiment of the present invention.

FIG. 9 is a sectional view of two containers according to FIG. 7 in anear coupled position.

FIG. 10 is a sectional view of two containers according to FIG. 7detachably coupled according to the first example of the secondembodiment.

FIG. 11 is a horizontal cross sectional view of an innermost portion ofthe cavity in a first or a second example of the second embodiment ofthe present invention.

FIG. 12 is a perspective view of a container according to a secondexample of the second embodiment of the present invention with a partialcutaway sectional view of the container.

FIG. 13A is a partially enlarged sectional view of two containerscoupled together according to the embodiment of a container shown inFIG. 12.

FIG. 13B is a partially enlarged perspective and sectional view of acontainer according to the embodiment of a container shown in FIG. 12.

FIG. 14 is a sectional view of a first container and a perspective viewof a second container in a third example according to the firstembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The First Example of the First Embodiment

With reference to FIGS. 1 to 3, parts shown in multiple figures have thesame identifier in each figure, and where an identifier is shown inmultiple figures it is intended to identify the same part in eachfigure. FIGS. 1 to 3 show a can 1 with a structure for detachablecoupling of cans in accordance with a first example of a firstembodiment of the present invention. The can 1 comprises a main body 15,a top 5, and a bottom with a peripheral wall 7. A flange 3 is anupstanding peripheral flange around the top 5 at which the top 5 and themain body 15 are seamed together. At the internal base of the flange 3is a trough 11, at the base of the flange 3, into which small amounts ofliquid on the top 5 of the can 1 settle. The top 5 includes an openingor removable tap 5 a that is nearest to the flange 3 at a pouringsection 20 where the user's lips would touch the can 1 when drinking aliquid. A tap handle 5 b, used for opening the removable tap 5 a, isattached to the top 5. The flange 3 extends upward a distance from thesurface of top 5. The flange 3, has a flange inner diameter which isshown in FIG. 1 with flared sections 9 radially flaring inwardly towardthe center of the top 5. Each of the flared sections 9 is formed bybending a section of the flange 3 inwardly toward the center of the top5 such that the innermost points of the flared sections 9 are inwardfaces 9 a. The distance between the inward faces 9 a defines a flareinner diameter. FIG. 1 is an example of the first embodiment with onlytwo flared sections 9 in the flange 3. However, the use of more flaredsections 9, formed to have the same flare inner diameter, is possible.As can be seen in FIG. 1, the flare inner diameter is smaller than theflange inner diameter.

As shown in FIG. 2, at the bottom end of the main body 15 of the can 1is the peripheral wall 7 extending from a shoulder 8 to an end face 7 e.The peripheral wall 7, comprises an outer wall surface as shown from theside view in FIG. 2, and an inner peripheral wall surface. Both theinner and outer wall surfaces of peripheral wall 7 are shown in crosssection in FIG. 3. The outer surface has a sloping profile from theshoulder 8 to the end face 7 e with a smaller outer diameter than themain body 15. Instead of sloping, the profile of the outer wall surfacemay be substantially parallel to the main body of the can. A center area2, inside the peripheral wall 7 at the bottom end of the can 1, isrecessed from the end face 7 e.

At equally spaced positions disposed around the outer surface of theperipheral wall 7, ridges 12 extend circumferentially around a portionof the outer surface of the peripheral wall 7. The number of the ridges12 corresponds to the number of the flared sections 9 on the top 5 ofthe can 1. In the example shown in FIG. 1, two ridges 12 at the bottomof can 1 correspond to the flared sections 9. Each of the ridges 12 isof at least approximately the same shape and size, so only one ridgewill be described herein. The ridges 12 run at least approximatelyparallel to and below the shoulder 8 along the outer surface of theperipheral wall 7 so as to define a void area 14 between the ridge 12and the shoulder 8. The void area 14 (i.e. groove) has an outer diametersmaller than the outer diameter of the ridges 12 and the main body 15.

At one end of each ridge 12 (shown as the right end in FIG. 2), a shortsegment 13 of the ridge 12 turns sharply upwardly toward the shoulder 8so as to form an L shape in the end of the ridge 12 and to create anending point 14 c of the void area 14. The short segment 13 may beseparated from the main part of the ridge 12 but still positioned toterminate the length of the void area 14. At a ridge mid-point 12 balong the length of the ridge 12 is a void mid-point 14 b of the voidarea 14. At the other end of the void area 14 formed by the adjacentridge 12 is a receiving point 14 a of the void area 14. At a positionadjacent to the end of the ridge 12 and the receiving point 14 a, asection 7 a of the peripheral wall 7 may have the regular slopingprofile shown in FIG. 2 without any of the ridges 12.

As shown in FIG. 3, which is a cross sectional view at the plane A-A ofthe can 1 of FIG. 1, the ridge outer diameter of the ridges 12 isgreater than the outer diameter of the peripheral wall 7 within the voidarea 14. The flare inner diameter, between the inward faces 9 a shown inFIG. 1, is about the same as the outer diameter in the void area 14 andsmaller than the outer diameter around the ridges 12.

When a first can 1 is longitudinally aligned end-to-end with a secondcan 1 according to FIG. 3 such that the flared sections 9 of the firstcan 1 are aligned with the wall sections 7 a, and the peripheral wall 7of the second can is inserted concentrically into the interior of theflange 3 of the first can 1, the end face 7 e of the peripheral wall 7of the second can 1 is near to or touching the top 5 of the first can 1.If the cans 1 are appropriately rotated in opposite directions withrespect to each other, the flared sections 9 will enter the receivingpoints 14 a. As the rotation continues, the flared sections 9 of thefirst can 1 move toward the ending points 14 c of the second can 1.Since the flare inner diameter between the inward faces 9 a is smallerthan the outer diameter of the ridges 12, the cans, having been rotatedinto this position, cannot be pulled longitudinally apart without firstreversing the rotation of the cans such that the flared sections 9return to the wall sections 7 a, to release the flared sections 9 fromthe void areas 14.

At the void ending point 14 c, near the short section 13, a lockingsection 12 c of each ridge 12 is created by a change in the shape orposition of that ridge 12 to increase the frictional contact betweenthat ridge 12 and the corresponding flared section 9, or between otherparts of the structure. The locking position 12 c secures the detachablecoupling of the cans until sufficient reverse rotational force isapplied to overcome the frictional resistance created by lockingposition 12 c. The secure detachable coupling allows multiple cans 1 tobe carried easily without the cans 1 becoming unintentionally detached.

Alternatively, the locking portion 12 c of the first example of thefirst embodiment may have at least one protuberance to create anincreased frictional resistance in the locking portion 12 c. Instead,near the position of the locking portion 12 c, the ridge 12 may have aswell for increased friction to prevent unintended decoupling by reverserotation under a small force. Further, each ridge 12 may have a numberof prominences on outer surface of the ridge 12 to increase thefrictional resistance in either direction of rotation with respect tothe corresponding flared section 9 of a first can 1.

Second Example of First Embodiment

The second example of the first embodiment uses the same structure atthe top end of the can 1, shown in FIG. 1, as the first example of thefirst embodiment. However, rather than using the bottom structure shownin FIGS. 2 and 3, the second example uses a bottom structure shown inFIGS. 4-6.

To simplify the description of the second example, the structure shownin FIGS. 4-6 will be described with reference to the first example ofthe first embodiment. In the first example, the outside diameter of theperipheral wall 7 is smaller than the inside diameter at the inwardfaces 9 a of the flared sections 9, and the ridges 12, protruding fromthe outer surface of the peripheral wall 7, have a larger outsidediameter than the peripheral wall 7.

In the second example of this embodiment, the outer diameter of theperipheral wall 7 is larger than the flare inside diameter. However, inthe second example, void areas 16, with receiving areas 17 and endpoints 16 d, circumferentially extend around the peripheral wall 7 toaccommodate the corresponding flared sections 9. Areas 19 are recessedinto the peripheral wall 7, between the end face 7 e at the bottom andthe shoulder 8 at the top, in an area wide enough to accommodate thewidth of the flared sections 9. Thus, the peripheral wall 7 of a firstcan 1 may be inserted concentrically into the center area of the flange3 of a second can 1 only if the recessed areas 19 are aligned with theflared sections 9. In addition, the void areas 16 of the second exampleare recessed into the surface of the peripheral wall 7 such that, withthe appropriate rotation described with respect to the first example,the flared sections 9 enter the void areas 16 to detachably couple therespective cans 1.

In the first example, as shown in FIG. 3, an upper surface 12 d of eachridge 12 contacts the corresponding flared section 9 when the cans 1 arecoupled together. In contrast, in the second example, a sloping surface16 b of each void area 16 contacts the inside of the correspondingflared section 9.

In addition, the downward slope of lower surface 16 b allows dirt orother particles to easily fall out of the circumferential voids 16.Accordingly, the circumferential voids 16 are unlikely to containparticles that could interfere with the insertion of flared sections 9into the circumferential voids 16.

Third Example of First Embodiment

The third example of the first embodiment, like the first and secondexamples, is a container having structures at both ends for the purposeof detachable coupling of at least two containers. Also, as in the priorexamples, after a first and second container are longitudinally aligned,a structure on a first end of the first container is inserted into astructure on a second end of a second container, a protrusion from aninner diameter of the structure on the second end of the secondcontainer engages a void on an outer diameter of a structure on thefirst end of the first container, and, by appropriately rotating therespective containers in opposite directions, the protrusion on thesecond container further engages the void on the first container toprovide a secure detachable coupling of the containers.

In this example, the container may be a plastic bottle or can. However,a container 51 will be described in the context of a plastic bottlehaving a top portion with an opening 65 and a top outer diameter that issmaller than the diameter of the main body of the container 51. Theouter surface of the top portion is threaded with a spiral thread 66around the outside of the top portion over a height 61 h, such that acap 52, having a corresponding threaded protrusion on its insideperimeter face, can be placed over and rotated (screwed) onto theoutside surface of the bottle top down to a cap band 52 p allowing thecap 52 to be securely fastened to seal the top of the container 51 in awell known manner. The outer surface of the cap 52 has a spiral thread64, similar to the spiral thread 66, running spirally around the cap 52.

On a bottom 54 of the container 51 in the third example, shown incross-section in FIG. 14, is a cavity 61 with a cylindrical shape havinga first region 61 b and a second region 61 c. The cavity 61 extends upinto the internal volume of the bottle from the center of the bottom 54.Both of the regions, 61 b and 61 c, having an inside wall 63 and atleast one threaded protrusion extending inwardly from their innersurfaces. The inside wall 62 of the first region 61 b has at least onethreaded protrusion 67 that is complementary to the thread 64 on theouter surface of the bottle cap 52, and it has an inside diameter suchthe bottle cap 52 may be screwed into the first region 61 b.

The second region 61 c extends deeper into the internal volume of thecontainer 51 from the innermost depth of the first region 61 b. Theinside wall 63 of the second region 61 c has a threaded protrusion 68complementary to the thread 66 on the outer surface of the top portionof the container 51, and it has an inside diameter such that the topportion of the container 51 may be screwed into the second region 61 c.

According to the third example of the first embodiment, a firstcontainer 51 and a second container 51 may be connected by a structurein which the cap 52 attached to the first container 51 is screwed intothe first region 61 b of the second bottle. Alternatively, a firstcontainer 51 and a second container 51 may be connected by a secondstructure in which the top portion of the first container 51, withoutthe cap 52, is screwed into the second region 61 c of the second bottle.

The total depth of the cavity 61 is approximately the sum of the depth61 h of the first region 61 b and the depth of the second region 61 c.Since the outer diameter of a rim 53 is larger than the outer diameterof the cap 52, the rim 53 will not fit into the first region 61 b. Thus,if the maximum depth of the cavity 61 is greater than the distance fromthe rim 53 to the opening 65 of the top portion of the container 51, therim 53 will stop further progress when it strikes the bottom surface 54of the container 51. The total depth of the cavity 61 is shared betweenthe first region 61 b and the second region 61 c so each region will beable to engage enough of the threads 64 and 66 to provide a secure,detachable coupling between the first and the second bottles 51 eitherwith or without the cap 52.

The cavity 61 may be limited to either the first region 61 b or thesecond region 61 c, rather than the combination described above.

The First Example of the Second Embodiment

FIG. 7 shows a perspective view of a top of the container 51 accordingto the first example of the second embodiment. The top portion of thecontainer includes the removable cap 52 and a neck 52 a, with both thecap 52 and the neck 52 a having an outside dimension that is smallerthan the main body 51. The neck 52 a extends up from the main body ofthe container 51 to the rim 53, which protrudes radially outward fromthe outer periphery of the top portion at a position above the neck 52a, as shown in FIG. 7, and a portion of the neck 52 a, having a smalleroutside dimension than the rim 53, extends below the rim 53 to the mainbody.

FIG. 8 shows a perspective view from a bottom of the container 51according to the first example of the second embodiment, including theoutline of the cavity 55 in the container bottom 54. The diameter of thecavity 55 at an interior wall 55 a is larger than the outside dimensionof the rim 53. At the opening of the cavity 55, extending inapproximately a same plane as the bottom 54, flexible protrusions ortabs 57 extend radially inward toward the center of the bottom 54,collectively forming a resilient flexible opening that is smaller thanthe outer dimension of the rim 53. The tabs 57 may be made of a samematerial as the container, or may consist of a different material thanthe container. In either case, the tabs 57 may be formed by casting,attached by gluing, welding or other techniques, or fitted to the otherelements of the structure. The number of tabs 57 forming the flexibleopening may vary. There is a gap 58 between adjacent tabs 57.

According to this example, the containers are coupled by longitudinallyaligning (i.e., aligning the longitudinal axes of) them, as in FIG. 9,and inserting the top portion of a first container 51 into the cavity 55in the bottom 54 of a second container 51, as in FIG. 10. As the topportion of the first container 51 is inserted into the flexible opening,the rim 53 comes into contact with the tabs 57. When sufficient force isprovided, the tabs 57 are deflected inward (into the cavity 55) and therim 53 will push into the flexible opening. The gaps 58 between therespective tabs 57 allow air, otherwise trapped inside the cavity 55when a top portion of the container 51 is inserted, to escape when thecontainers are pushed together. The inner diameter and the depth of thecavity 55 are large enough to allow the rim 53 and the top portion,including the cap 52, above the rim 53 to enter the cavity 55 far enoughthat the rim 53 pushes past the tabs 57. The cavity 55 may include anouter region 55 b having a diameter large enough to fit the rim 53, andan inner region 55 c having a diameter only large enough to fit the capor top portion above the rim 53. Reserve space 56 in each of the outerregion 55 b and the inner region 55 c, provides the room needed so therim 53 can push past the flexible tabs 57 when the tabs 57 bend into thecavity 55. In general, as shown in FIGS. 8-10, the inside profile ofcavity 55 conforms to the outside profile of the top portion, except forthe reserve space 56. The reason for this will be explained in moredetail below.

Once the rim 53 has been forced through the flexible opening, the tabs57 will resiliently rebound, to the extent possible, back toward theirundeflected positions in the plane of the bottom 54, but may come torest against the outside of the neck 52 a, as in FIG. 10, if thediameter of the neck 52 a is also larger than the inner diameter of theflexible opening when the tabs 57 are in their undeflected position. Thetabs 57 are flexible enough to allow the diameter of the rim 53 to beinserted into the cavity 55 as described above. However, the rigidity ofthe tabs 57 determines how easily the containers 51 can be attached anddetached in the manner described above. Therefore, depending on thematerial, the tabs 57 may not be rigid enough to prevent theunintentional decoupling of the containers 51 under a small force, ortoo rigid to allow the easy attachment and detachment of the containers51. It is preferable that a minimum force necessary to pull the rim 53through the flexible opening is large enough to provide a securedetachable coupling while still allowing the containers to be pulledapart without a need for excessive effort.

As stated above, the interior of the cavity 55 conforms closely to theexterior shape of the top portion, such that the top portion fits snuglyinto the cavity 55. Frictional resistance between the cap 52 and theinner walls 55 e of the inner region 55 c of the cavity 55 increases theminimum force required to attach and detach the containers 51. Toincrease this resistance, the interior walls 55 e of the cavity 55 mayinclude deformable sections 55 f, having the horizontal cross sectionshown in FIG. 11, such that the inner diameter defined by the deformablesections 55 f is smaller than the outer diameter of the top portion(i.e. cap 52). Due to the smaller diameter of the deformable sections 55f, insertion of the top portion into the cavity 55 requires temporaryresilient deformation of the deformable sections 55 f. The resilientdeformable sections 55 f squeeze the exterior of the top portion,increasing the holding force of the connection, and opposing theunintended withdrawal of the top portion from the cavity 55. The spaces55 h between the deformable sections 55 f allow air, otherwise trappedinside the region 55 c when a top portion of the container 51 isinserted, to escape from the cavity 55.

Characteristics affecting the rigidity of the tabs 57 also affect thestrength of the coupling. For example, varying the composition, number,shape, length, width and/or thickness of the tabs 57 or varying thegeometries of the gaps 58 between the tabs 57, affects the strength ofthe coupling. Similarly, the characteristics of the deformable sections55 f affect the frictional resistance provided against insertion,removal, or rotation of the top portion of the containers 51 coupledaccording to this example. The coupling and decoupling of the containers51 according to this example may be performed repeatedly without damageto the containers 51 or deterioration of the coupling parts.

Second Example of the Second Embodiment

In the second example of the second embodiment, the top portion of thecontainer 51 is the same as in the first example of the secondembodiment. However, in the structure at the bottom of the container 51in the second example, shown in a cut-away perspective view in FIG. 12,the tabs 57 of the first example are replaced by flexible flanges 59,which extend from the opening of the cavity 55, into the depth of thecavity 55 along the inside walls of the region 55 b. A number of theflexible flanges 59 are spaced apart around the inside wall of theregion 55 b. The spaces between the respective flexible flanges 59 allowair, otherwise trapped inside the cavity 55 when a top portion of thecontainer 51 is inserted, to escape when two containers 51 are attachedby this structure.

As shown in a partial cross section view in FIG. 13 a, the flexibleflanges 59 include a projection 60 having a tapered face 60 a such thatthe flexible flange 59 is thin at the opening of the cavity 55 andbecomes gradually thicker with the increasing depth of the outer region55 b, until a seated position 55 k in which the thickness of theflexible flange 59 abruptly becomes thin again. FIG. 13 b illustrates anexample container top portion prior to insertion into the outer region55 b of the container illustrated in FIG. 13 a. As the container topportion is inserted into the outer region 55 b by moving the containertop portion in the direction of the arrow illustrated in FIG. 13 b, theflexible flanges 59 are gradually deformed in a direction A by the rim53 until the rim 53 pushes past a thickest portion 60 b of the flexibleflanges 59 into the position 55 k. As the rim 53 moves past the thickestpoint 60 b to the seated position 55 k, the thickness of the flexibleflanges 59 sharply decreases, the diameter of the region 55 b increasesto accommodate the rim 53, the deformed flange 59 moves in a direction Btoward the neck 52 a, and the rim 53 is moved into the seated position55 k. The gradually increasing slope of tapered face 60 a providesgradually increasing resistance as the rim 53 is inserted. However, whenwithdrawing the top portion from the position 55 k, a relatively highresistance is immediately encountered at the thickest portion 60 b ofthe flexible flanges 59, due to the sharply decreasing diameterencountered when exiting the region 55 k. Thus, the force required toinsert the top portion of the first container 51 into the bottomstructure of the second container 51 is much lower than the forcerequired to pull the containers apart. The second example of the secondembodiment performs in a similar manner to the first example usinganother structure and method for securely and detachably couplingcontainers.

Although the preferred examples and embodiments of the present inventionhave been disclosed for illustrative purposed, those skilled in the artwill appreciate that various modifications, additions, and substitutionsare possible without departing from the scope and spirit of theinvention as defined by the accompanying claims.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:
 1. A container comprising: a main body that, inuse, holds liquid; a top portion having an upstanding peripheral flange,the upstanding peripheral flange having at least one protrusionextending radially from a surface; and a bottom portion having aperipheral structure, the peripheral structure having an end face, aninterior wall facing toward a recessed area, an exterior wall, and atleast one groove circumferentially oriented on the interior or exteriorwall to receive at least one protrusion of a second container, the atleast one groove having a receiving portion which, when aligned with theat least one protrusion of the second container, receives the at leastone protrusion of the second container upon rotation of the secondcontainer with respect to the container to detachably couple thecontainer and the second container, and the at least one groove furtherincluding a locking portion and a blocking portion, wherein the at leastone groove exists between the main body and a protrusion extendingcircumferentially around the exterior wall of the bottom portion, thereceiving portion is an opening at one end of the at least one groove,and the blocking portion is an obstructed end of the at least onegroove.
 2. The container according to claim 1, the top portion furthercomprising: a tap removable from an opening in a top surface near apouring section of the upstanding peripheral flange, wherein, thelocking portion is adjacent to the blocking portion and causes anincrease in rotational friction, and at least one bent section of theupstanding peripheral flange bent radially inward forms the at least oneprotrusion, the bent section of the upstanding peripheral flange isdisposed separate from the pouring section.
 3. The container accordingto claim 2, further comprising: a projection at one end of thecircumferential protrusion, wherein the projection obstructs the end ofthe circumferential groove to form the blocking portion.
 4. Thecontainer according to claim 3, wherein the projection extends from thecircumferential protrusion to form an L-shaped protrusion.
 5. Thecontainer according to claim 2, wherein the circumferential protrusionangles toward the main body, such that the at least one groove isnarrower on one end.
 6. The container according to claim 5, wherein theat least one groove is narrowed to form a blocking position.
 7. Thecontainer according to claim 2, wherein the circumferential protrusionbecomes wider on one end, such that the at least one groove is narrowedby the wide end of the circumferential protrusion.
 8. The containeraccording to claim 7, wherein the at least one groove is narrowed toform a blocking position.
 9. The container according to claim 2, whereinthe circumferential protrusion having at least one projection or atleast one swell on an exterior surface of the circumferential protrusionbetween the receiving portion and the blocking portion.
 10. Thecontainer according to claim 1, wherein the container is a beverage can.